Have a look on the tyre if it says re40 or re50 they are basically the oem tyre. What is the best tyre is up for for discussion! Bridgestones are good but not cheap re50 are the newer model and considered a lot better.
Blackcircles.com is a a good place to start. Pretty user friendly and you can order and pay for fitting at a local supplier all online. Other brands of tyre worth considering include vredstien, falken, continental, toyo and many more. Have a look in the subforum for recomendations or there are many tyre review sites. But if you are wanting to stay same on all four youll need to know exactly which bridgestones you have.
Remember you tend to get what you pay for